Genetic immunization against neu/erbB2 transgenic breast cancer

erbB2/neu, an overexpressed oncogene product, has been proposed as a human cancer vaccine target. In the present study, transgenic (rat neuNT oncogene ) FVB/neu mice, developing metastasizable mammary carcinoma, were immunized with a plasmid DNA encoding are not tolerant to the self antigen and seque nces. We report that transgenic tumour-bearing mice: like some breast cance r patients erbB2 + X, develop anti-neu autoimmune responses, which can be b oosted and skewed to a Thl phenotype by DNA immunization. Intramuscular inj ections of neuNT plasmid. drastically reduced (or even prevented in a small number of treated mice) the outgrowth of mammary neoplasms as well as thei r metastatic penetrance. Furthermore, DNA immunization caused haemorrhagic necrosis of established cancer nests, leaving a greatly reduced portion of the tumour burden for the host to cope with. The antitumour activities we o btained, in this very challenging model for cancer immunotherapy, lay the f oundation for DNA-based immunization to control erbB2/neu-overexpressing ne oplasms.